There are already known various constructions of arrangements for solder-coating the leads of electrical or electronic components, among them such that perform the solder-coating operation in a fully automated manner. So, for instance, it is known to cause a fixture which is loaded with the components to travel in a course that has such a predetermined and precisely maintained relationship with respect to an area of the upper surface of a molten solder bath that the leads of the components, which project downwardly from the fixture, penetrate into or are dipped in the molten solder bath at the aforementioned area to the extent required to coat the desired lengths of such leads in their entirety with the molten solder. For this approach to be successful, that is, to achieve the requisite solder-coating to the desired point, such as up to the so-called frit area, of each of the components, it is mandatory that the extent to which the leads penetrate into the molten solder bath be maintained substantially invariable over time, that is, from one solder-coating operation to another throughout even a very lengthy series of such operations. To be able to achieve this result, it was necessary when using the heretofore known approaches to employ for the conveyance of the fixture in the required course conveying or other handling equipment that operates with a very high degree of precision (and, consequently, is very expensive) and also to take appropriate measures to assure that the spatial position of the aforementioned area of the molten solder upper surface with respect to the course of travel of the loaded fixture remains the same even as the molten solder is being depleted or replenished (which again adds to the cost of the equipment). Thus, it may be seen that the conventional equipment leaves much to be desired in terms of cost or quality.
Accordingly, it is a general object of the present invention to avoid the disadvantages of the prior art.
More particularly, it is an object of the present invention to provide a solder-coating arrangement which does not possess the disadvantages of the known arrangements of this kind.
Still another object of the present invention is so to construct the solder-coating arrangement of the type here under consideration as to achieve reliable and repeatable solder-coating results over the entire useful lifetime of the arrangement.
A further object of the present invention is to design the arrangement of the above type in such a manner as to be relatively simple in construction, inexpensive to manufacture, easy to use, and yet reliable in operation.
It is yet another object of the present invention to devise a fixture that is especially suited for use in the solder-coating arrangement of the above type but can be used independently thereof as well, which fixture is constructed to assure accurate and reliable solder-coating of only the desired portions of the components carried by the fixture even if the fixture is handled in less than careful or precise manner during the solder-coating operation.
A concomitant object of the present invention is to develop a method of solder-coating the end portions of electrical or electronic components, which method brings about accurate and repeatable solder-coating results.